The present invention relates to a propeller for gaseous and fluidic media, particularly an air propeller.
Air propellers of the foregoing type normally have at least one rotatable vane. An air propeller disclosed in DE-PS 867,498 has a vane comprised of two propeller blades. These blades are spaced from each other and have a common shaft to which the blades are connected. Both propeller blades in this known air propeller extend parallel to each other whereby the central axis of elongation of the vane lies approximately in the middle of the distance between the blades. The propeller is formed as an adjusting propeller, in which acting centrifugal moments, due the above described construction, are substantially reduced or totally eliminated. The disadvantage of this otherwise satisfactory known propeller resides in that the individual blades which extend right from the center of rotation of the propeller of the vane as very thin blades are subjected to high centrifugal forces and thus high loads, particularly when the vane is rotated with high speeds. In the region of the blades, axial dimensions are twice as great as those of the single-vane air propeller; this can be also a serious disadvantage.
No increase in a thrust value and thus no load increase can be obtained with the above described conventional adjusting propeller. Sound emission of such a propeller exceeds permissible values.